Over the years we have come across this and variations of it.
We had a company blind pricing houses in a very affluent area where we have a few hundred customers. We had this job at £23 and have been doing it for years for them and even before them the original customer for maybe a further 5 years.
Its a 5 bed house with a nice large single storey extension nice lot of windows on the rear with 6 skylites. IT takes no more than 20 minutes to do.
The card put through the door was for £12!! Obviously the guys hadnt seen the rear and the customer queried our price, i just put it to them that if you pay £12 you'll get £12 worth of cleaning, feel free to contact them if you like i said but i bet once theyve seen the rear it wont be £12!!
And another just round the corner, nice big bungalow £21, again been going years and years there, we got underpriced by a few quid so customer rang thanked us for our service throughout the years and canned us.
A few months later and a rather apologetic phone call asking us to return to clean the windows, upon asking why, the other guys broke the gate climbing over and once charged for the rears even though it wasnt done!!
They couldnt kiss our ass enough, wife told hubby off as it was his decison to save a few quid!!! LOL
I think most people know if they want a decent job doing its worth paying for it